1. Field of the Invention
The present invention relates to a photovoltaic element, a photovoltaic module comprising the photovoltaic element, and a method of fabricating the photovoltaic element, and more particularly, it relates to a photovoltaic element comprising a transparent conductive film including an indium oxide layer, a photovoltaic module comprising the photovoltaic element, and a method of fabricating the photovoltaic element.
2. Description of the Background Art
A photovoltaic element comprising a transparent conductive film including an indium oxide layer is known in general as disclosed in Japanese Patent Laying-Open No. 2004-281586, for example.
In the aforementioned Japanese Patent Laying-Open No. 2004-281586, there is disclosed the photovoltaic element (photovoltaic element) comprising a photoelectric conversion layer and the transparent conductive film formed on a surface of the photoelectric conversion layer and consisting of an indium tin oxide (ITO) layer having two X-ray diffraction peaks. In the photovoltaic element, the two X-ray diffraction peaks of the indium tin oxide layer include a peak on a low angle side and a peak on a high angle side having an intensity level higher than the peak on the low angle side.
In the photovoltaic element disclosed in the aforementioned Japanese Patent Laying-Open No. 2004-281586, the transparent conductive film is so formed that the indium tin oxide layer has the two X-ray diffraction peaks of the peak on the low angle side and the peak on the high angle side having the intensity level higher than the peak on the low angle side, whereby the resistance of the transparent conductive film can be reduced as compared with a case where the indium oxide layer has only one X-ray diffraction peak. In addition, the transparent conductive film is formed in the aforementioned manner, light absorption loss of the transparent conductive film can be reduced as compared with the case where the indium oxide layer has only one X-ray diffraction peak. In the photovoltaic element (photovoltaic element), it is known that the transparent conductive film having low resistance and low light absorption loss is effective in increasing the cell output (Pmax) of the photovoltaic element. In the photovoltaic element disclosed in the aforementioned Japanese Patent Laying-Open No. 2004-281586, the resistance and the light absorption loss of the transparent conductive film can be reduced as compared with the case where the indium oxide layer has only one X-ray diffraction peak, whereby the cell output (Pmax) of the photovoltaic element can be increased.
In the photovoltaic element disclosed in the aforementioned Japanese Patent Laying-Open No. 2004-281586, however, sufficient studies on weather resistance have not been made. Thus, it is disadvantageously difficult to improve the weather resistance.